Pendent residential fire protection sprinklers

1. A pendent residential fire prevention sprinkler comprising:

a sprinkler body, having an inlet and an outlet and an axial passage from said inlet to said outlet, said inlet being to receive in-flowing fire-extinguishing fluid and said outlet being to deliver the fluid from said body;

means for blocking and unblocking said outlet to prevent the fluid from passing through said outlet, said means being for blocking said outlet until occurrence of a predetermined condition and for unblocking said outlet in response to occurrence of the condition;

a frame structure extending from said sprinkler body; and

a deflector, supported by said frame structure at a predetermined distance from said outlet, at a position to be impinged upon by the fluid leaving said outlet upon said outlet being unblocked,

said deflector having a central portion and a peripheral portion, said peripheral portion having a number of slots extending from an open end, at the periphery of said deflector, generally toward said central portion, and each having a closed end,

said slots including a first plurality of slots each of which extends inward from the periphery of said deflector with a first, uniform width between the periphery and said closed end of that slot, and said closed ends of said first plurality of slots narrowing from said first, uniform width to zero width, and

said slots including a second plurality of slots each of which has a first portion and a second portion between the periphery of said deflector and said closed end portion of that slot, said first portion having a width that varies at different points within said portion, and said second portion having a uniform width, wherein said first portion is radially outward from said second portion from said central portion of said deflector.

2. A sprinkler in accordance with claim 1 , further comprising a hub assembly supported at a position between said outlet and said central portion of said deflector and at a second predetermined distance from said outlet, whereby fluid leaving said outlet impinges on said hub assembly before impinging on said deflector, said hub assembly having a hub and having a tip that protrudes from said hub, and wherein said tip and said hub each have angled lateral surfaces.

3. A sprinkler in accordance with claim 2 , wherein said hub assembly comprises a screw threadedly received in a central bore of said hub, and wherein said tip is a tip of said screw.

4. A pendent residential fire prevention sprinkler comprising:

a sprinkler body, having an inlet and an outlet and an axial passage from said inlet to said outlet, said inlet being to receive in-flowing fire-extinguishing fluid and said outlet being to deliver the fluid from said body;

means for blocking and unblocking said outlet to prevent the fluid from passing through said outlet, said means being for blocking said outlet until occurrence of a predetermined condition and for unblocking said outlet in response to occurrence of the condition;

a frame structure extending from said sprinkler body; and

a deflector, supported by said frame structure at a predetermined distance from said outlet, at a position to be impinged upon by the fluid leaving said outlet upon said outlet being unblocked,

said deflector having a central portion and a peripheral portion, said peripheral portion having a number of slots extending from an open end, at the periphery of said deflector, generally toward said central portion, and each having a closed end portion,

said slots including a first plurality of slots each of which extends inward from the periphery of said deflector with a uniform width between the periphery and said closed end portion of that slot, and

said slots including a second plurality of slots each of which has a first portion and a second portion between the periphery of said deflector and said closed end portion of that slot, said first portion having a width that varies at different points within said portion, and said second portion having a uniform width,

wherein said first plurality of slots comprises three groups of slots, said slots of a first of said three groups having a first length and a narrow width, said slots of a second of said three groups having a second length and that is less than said first length and a width that is greater than said narrow width, and said slots of a third of said three groups having a length that is less than said length of said slots of said second group and a width that is greater than the widths of said slots of said first and second groups.

5. A sprinkler in accordance with claim 4 , wherein said frame structure comprises two frame arms lying in a first plane that extends from said outlet to said hub assembly, and wherein two of said slots of said first group are located in said plane and two others of said slots of said first group are located in a plane perpendicular to said first plane,

and wherein said second group of slots includes eight slots one of which is disposed to each side of each of said slots of said first group and spaced therefrom around the periphery of said deflector by an angle of 15°,

and wherein said third group of slots includes four slots located between two slots of said second group of slots and equally space therefrom around the periphery of said deflector.

6. A sprinkler in accordance with claim 5 , wherein each of said slots of said second plurality also has a third portion, in which that slot has a uniform width and in which said slot extends in toward said central portion of said deflector in a direction that does not lie on a radius of said deflector.

7. A sprinkler in accordance with claim 5 , wherein said second plurality of slots includes eight slots each of which is located between a slot of said second group of slots and a slot of said third group of slots, at a location about 32.5° from a slot of said first group of slots.

8. A sprinkler in accordance with claim 1 , having a K-factor of at least 7.0.

9. A sprinkler in accordance with claim 8 , having a K-factor of at least 7.6.

10. A sprinkler in accordance with claim 1 , where said deflector has a plurality of holes that pass through said deflector, each of said holes being spaced angularly by more than 10° and less than 80° from a slot of said second plurality of slots.

11. A sprinkler in accordance with claim 10 , wherein said holes are angularly spaced about 22.5 from a slot of said second plurality of slots.

12. A fire protection system comprising a plurality of sprinklers in accordance with claim 1 .

13. A residential fire protection system comprising:

a plurality of residential fires sprinklers having a K-factor of at least 7.0; and

at least one conduit for delivering a fire extinguishing fluid to said sprinklers,

wherein said residential fire sprinklers each comprise:

a sprinkler body, having an inlet and an outlet and an axial passage from said inlet to said outlet, said inlet being to receive in-flowing fire-extinguishing fluid and said outlet being to deliver the fluid from said body;

means for blocking and unblocking said outlet to prevent the fluid from passing through said outlet, said means being for blocking said outlet until occurrence of a predetermined condition and for unblocking said outlet in response to occurrence of the condition;

a frame structure extending from said sprinkler body; and

a deflector, supported by said frame structure at a predetermined distance from said outlet, at a position to be impinged upon by the fluid leaving said outlet upon said outlet being unblocked,

said deflector having a central portion and a peripheral portion, said peripheral portion having a number of slots extending from an open end, at the periphery of said deflector, generally toward said central portion, and each having a closed end portion,

said slots including a plurality of slots each of which has a first portion and a second portion between the periphery of said deflector and said closed end portion of that slot, said first portion having a width that varies approximately linearly within said portion, decreasing from the periphery of said deflector, and said second portion having a uniform width and extending at an angle to a radius of said deflector that extends from that slot to said central portion of said deflector, wherein said first portion is radially outward from said second portion from said central portion of said deflector,

and wherein said residential fire sprinklers each provide a fluid flow of 40 gallons per minute at a gauge fluid pressure of 27.7 psi.